Compatible with DeWalt 18V/20V Max battery converter with top port for use with Milwaukee M18 18V cordless power tools. NOTE: The battery adapter is not compatible with heavy duty tools. DeWalt battery adapter compatible with Milwaukee M18, can be converted to DEWALT 18V-20V lithium battery, compatible with Milwaukee power tool batteries, a perfect replacement for Milwaukee 18-volt lithium battery. Helpful Hints: Cannot be used to charge power tool batteries, the adapter is only suitable for any charger. This adapter has a built-in battery lock and protective circuit board (PCBA). This battery adapter converts to Dewalt 18V/20V Max lithium batteries, compatible with Milwaukee power tools with M18 18V batteries (Not suitable for Milwaukee NICD V18 18V tools). The adapter is suitable for tools with a battery that hangs freely in an open area, but cannot be used in an enclosed area such as a flare. If the 18V Li-Ion battery stops working, use an adapter compatible with Dewalt 18V or 20V